Pregnancy blood test, that is, after pregnancy to extract venous blood to do blood HCG examination, or check the blood HCG and progesterone value, if there is a blood HCG value elevated more than 5U / L or more, progesterone value also shows elevated situation, indicating that it is pregnant. Generally in the early stages of pregnancy pregnant women blood tests, blood HCG values will be doubled every other day, indicating that the probability of intrauterine pregnancy is relatively large, it is recommended that women who usually have regular menstrual periods, in the menstrual period delayed one week later, go to the hospital to do blood HCG tests and gynecological ultrasound, to diagnose whether or not pregnancy, and at the same time need to confirm whether or not it is an intrauterine pregnancy to rule out the case of ectopic pregnancy, blood tests to check the value of HCG. Generally in about 10 days after intercourse can diagnose whether pregnancy, high sensitivity and more accurate, to determine is pregnant, pregnant women can take folic acid, to prevent fetal neural tube development malformation, and regular pregnancy test.